Abstract
Burst loss is a critical issue in Optical Burst Switching (OBS) networks which restrains its deployment. This article presents a novel routing and wavelength assignment strategy for the Cooperative Clustered OBS (C2OBS) network architecture, to proactively avoid contention. In C2OBS, the network topology is divided into several manageable overlapping zones/clusters, with a Zone Head (ZH) node keeping an information base of zone resources. The ZH pre-computes a list of alternate k-shortest disjoint paths for every ingress-egress node pair within the zone. The ZH utilizes both the inferred knowledge about wavelength usage at the zone intermediate nodes and a novel poles apart heuristic for assigning wavelengths to incoming bursts. A route is selected among the pre-computed paths where the selected wavelength is available. As a result, traffic is balanced among the set of pre-computed routes, thus proactively reducing probability of contention. This strategy is called Resource Aware Routing (RAR) and Intelligent Wavelength Assignment (IWA).

Abstract
In this work, an in-depth analysis concerning the transmission performance of IEEE802.11g/n WiFi signals in a radio-over-fiber system is presented. Low-cost optical/electrical transceivers based on 850 nm vertical cavity surface emitting lasers (VCSELs) and PIN photodiodes are considered. System modelling includes the impact of noise generated in the optical path, such as relative intensity noise (RIN), shot noise, photodetector thermal noise, clipping and intermodulation distortion. Analytic results based on Volterra series analysis for the performance of the system in terms of SNR and EVM for several optical modulation index values are obtained. The theoretical analysis is also compared with experimental results. Among several conclusions, it is observed that the laser intermodulation distortion, clipping and RIN are the most relevant factors.

Abstract

Abstract
This paper analyzes experimentally the limitations observed in lightwave systems using distributed Raman amplifiers operating under large pump power input conditions. The Brillouin effect is observed as the pump power becomes equal to watt centered in a specific pump wavelength. The presence of Brillouin peaks degrades the system performance. The Raman amplifier is set with singlemode and dispersion compensating fibers and evaluated in a high capacity WDM link at transmission rates up to 40 Gb/s per channel. The dispersion compensation was accomplished by adjusting the length of the dispersion compensating fiber. The system and amplifier characterization were developed in terms of the on-off gain, ripple, optical signal-to-noise ratio, eye diagram and extinction ratio.

Abstract
This article analyzes experimentally the limitations observed in lightwave systems using distributed Raman amplifiers operating under large pump power input conditions. The Brillouin effect is observed as the pump power reaches 1 W. The presence of Brillouin peaks degrades the performance of the system. The Raman amplification occurs in single mode and dispersion compensating fibers, being evaluated in a link at transmission rate of 40 Gb/s. (C) 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1331-1335, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25162

Abstract
This article analyzes experimentally the limitations observed in a 45 km Raman amplified 4 x 40 Gb/s transmission system operating under multiple pump and single high pump power configurations. A signal-to-noise ratio of 19.2 dB, an extinction ratio of 10.4 dB and a jitter of 1097 fs are achieved for moderate pump powers and higher order stimulated Brillouin scattering lines give rise to system degradation for pump power levels more than 0.5 W. (C) 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:14031407, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26827